The present invention relates to a closure device for an inlet line of a liquid tank in motor vehicles which prior to the supply of liquid into the inlet line is adapted to be moved from a closing position into an open position and subsequent thereafter again into the closing position.
Such liquid tanks are used, for example, as the fuel tank or as the tank for the cooling liquid of the internal combustion engine. Other tanks or reservoirs may serve for storing the engine oil, the transmission oil or also cleaning liquid. With known closure devices, there exists in principle the danger that they are not adequately fastened and may be lost during a drive. It is already known to arrange the closure device in a housing which is closed by a flap, for example, the so-called tank flap. However, this requires an additional expenditure. The difficulties are enhanced in particular when it is intended to simplify the fuel intake and Possibly even to automate the same. Proposals in that direction can be found, for example, in the DE-PS 29 29 192. The problem thereby exists in principle to so construct the closure device that it enables in a simple manner both the filling of the liquid tank as also the closing of the inlet line.
The present invention is concerned with the task to provide a closure device of the aforementioned type which avoids the aforementioned disadvantages with constructively simple means and provides a significant contribution for the automation of the fuel input, i.e., for tanking.
The underlying problems are solved according to the present invention in that the closure device is seated on the inlet line in an undetachable manner, in that the closure device possesses a through-opening corresponding to the inlet line opening and in that the through opening is arranged aligned with the inlet line in the open position and is arranged beyond the inlet line opening in the closing position.
The non-detachability of the closure device represents a marked advantage compared to the known closure devices because a possibly open inlet line can be closed again at any time by the always present closure device. The movability of the closure device between the closing and the open position in conjunction with the interplay of through-opening and inlet line opening offers in a simple manner the possibility to do justice to the two essential tasks notwithstanding the non-detachability of the closure device; namely, to possibly completely open up the inlet line opening and to also completely close the same again. This can take place in a simple manner, possibly also with the aid of a manipulator, exclusively by the movement of the closure device from one position into the other.
This movement may be both a linear movement as also a rotary movement. The latter offers the advantage, especially as regards a movement of the closure device with the aid of a manipulator, to be possible with relatively small force expenditure and therewith to carry out the movement also under unfavorable climatic conditions during which the movability of the closure device is rendered more difficult by increased friction forces.
The movability of the closure device can be facilitated additionally by a marking which is opened up along its circumference in the closing and in the open position. It becomes possible with the assistance of a suitable receiver or pick-up for the position of the marking and by the shape of the marking freed or laid open by the closure device, to undertake the movement, respectively, to control by a manipulator during a movement.
In particular for the latter application, a further improvement results from an arrangement of the closure device in a housing which is closed off against the outside by a flap permeable to radiation of defined wavelength. The radiation emitted by a suitable device passes through the material of the flap which is possibly impermeable for visible light, and impinges on a suitable sensor arranged, for example, inside of the housing. A transmitting/receiving device may be provided supplementarily in the motor vehicle which signals the impingement of the radiation on the sensor and is used for the adjustment of the manipulator. Additionally, also an opening device for the flap can be controlled by the sensor which frees the access of the manipulator to the closure device.